Left to Right: Mrs Franklin D. Roosevelt; King George VI of England; Mrs. Sarah Roosevelt; Queen Elizabeth (the "Queen Mother"); and President Roosevelt.
In June of 1939, King George VI became the first reigning British monarch to visit the United States. The trip featured all the staples of a royal visit: a sight-seeing tour of Washington, a formal State Dinner, and a big bash at the British Embassy, of which Representative Charles J. Bell said, "It was sort of like our church socials in Missouri."
And towards the end of the trip, the Roosevelts invited the royals to Hyde Park for hot dogs. Here's what else was on the menu:
MENU FOR PICNIC AT HYDE PARK
Sunday, June 11, 1939
Hot Dogs (if weather permits)
Coffee, Beer, Soft Drinks
[Source: FDR Presidential Library & Museum]
So if your Fourth of July plans involve hot dogs (or cranberry jelly), you can honestly say you're eating like a king. Happy Fourth!
Franklin Delano Roosevelt chauffeurs Queen Elizabeth, her husband King George VI, and his daughter-in-law, Betsey Roosevelt.
The FDR Library has lots more on the royal visit:
FDR's original invitation (pages one and two)
Transcript of King George VI's Handwritten Notes for a Memorandum on His Conversations with President Roosevelt on June 10 and 11, 1939
FDR's thank you telegram to King George VI
And you can read more general background on the visit here.